3-phenyl-4-p-tolyloxysulfonyl-sydnone

4-benzylsulfamoyl-3-phenyl-sydnone

4-(4-chloro-phenoxysulfonyl)-3-phenyl-sydnone

4-(4-bromo-phenoxysulfonyl)-3-phenyl-sydnone

4-(morpholine-4-sulfonyl)-3-phenyl-sydnone